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400 AMD Geode™ SC3200 Processor Data Book
Electrical Specifications
32581C
9.3.9 Universal Serial Bus (USB) Interface
Table 9-28. USB Timing Parameters
Symbol Parameter Min Max Unit Figure Comments
Full Speed Source (Note 1, Note 2)
t
USB_R1
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Rise Time
4 20 ns 9-37 (Monotonic) from 10% to
90% of the D_Port lines
t
USB_F1
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Fall Time
4 20 ns 9-37 (Monotonic) from 90% to
10% of the D_Port lines
t
USB_FRFM
Rise/Fall time matching 90 110 %
t
USB_FSDR
Full-speed data rate 11.97 12.03 Mbps Average bit rate 12 Mbps
± 0.25%
t
USB_FSF
Full-speed frame interval 0.9995 1.0005 ms 1.0 ms ± 0.05%
t
period_F
Full-speed period between data bits 83.1 83.5 ns Average bit rate 12 Mbps
t
USB DOR
Driver-output resistance 28 43 W Steady-state drive
t
USB_DJ11
Source differential driver jitter for con-
secutive transition
–3.5 3.5 ns 9-38 Note 3, Note 4
t
USB_DJ12
Source differential driver jitter for paired
transitions
–4.0 4.0 ns 9-38 Note 3, Note 4
t
USB_SE1
Source EOP width 160 175 ns 9-38 Note 4, Note 5
t
USB_DE1
Differential to EOP transition skew –2 5 ns 9-39 Note 4, Note 5
t
USB_RJ11
Receiver data jitter tolerance for con-
secutive transition
–18.5 18.5 ns 9-40 Note 4
t
USB_RJ12
Receiver data jitter tolerance for paired
transitions
–9 9 ns 9-40 Note 4
Full Speed Receiver EOP Width (Note 4)
t
USB_RE11
Must reject as EOP 40 ns 9-39 Note 5
t
USB_RE12
Must accept as EOP 82 ns 9-39 Note 5
Low Speed Source (Note 1)
t
USB_R2
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Rise Time
75 300
(Note 6)
ns 9-37 (Monotonic) from 10% to
90% of the D_Port lines
t
USB_F2
DPOS_Port1,2,3, DNEG_Port1,2,3
Driver Fall Time
75 300
(Note 6)
ns 9-37 (Monotonic) from 90% to
10% of the D_Port lines
t
USB_LRFM
Low-speed Rise/Fall time matching 80 120 %
t
USB_LSDR
Low-speed data rate 1.4775 1.5225 Mbps Average bit rate 1.5 Mbps
± 1.5%
t
PERIOD_L
Low-speed period 0.657 0.677 μs at 1.5 Mbps
t
USB_DJD21
Source differential driver jitter for con-
secutive transactions
–75 75 ns Host (downstream),
Note 4
t
USB_DJD22
Source differential driver jitter for paired
transactions
–45 45 ns 9-38 Host (downstream),
Note 4
t
USB_DJU21
Source differential driver jitter for con-
secutive transaction
–95 95 ns 9-38 Function (downstream),
Note 4